Buggy code:
public class FastFourierTransformer implements Serializable { static final long serialVersionUID = 5138259215438106000L ; private FastFourierTransformer . RootsOfUnity roots = new FastFourierTransformer . RootsOfUnity ( ) ; public FastFourierTransformer ( ) { } public Complex [ ] transform ( double [ ] f ) throws IllegalArgumentException { } public Complex [ ] transform ( UnivariateRealFunction f , double min , double max , int n ) throws IllegalArgumentException , FunctionEvaluationException { } public Complex [ ] transform ( Complex [ ] f ) throws IllegalArgumentException { } public Complex [ ] transform2 ( double [ ] f ) throws IllegalArgumentException { } public Complex [ ] transform2 ( UnivariateRealFunction f , double min , double max , int n ) throws IllegalArgumentException , FunctionEvaluationException { } public Complex [ ] transform2 ( Complex [ ] f ) throws IllegalArgumentException { } public Complex [ ] inversetransform ( double [ ] f ) throws IllegalArgumentException { } public Complex [ ] inversetransform ( UnivariateRealFunction f , double min , double max , int n ) throws IllegalArgumentException , FunctionEvaluationException { } public Complex [ ] inversetransform ( Complex [ ] f ) throws IllegalArgumentException { } public Complex [ ] inversetransform2 ( double [ ] f ) throws IllegalArgumentException { } public Complex [ ] inversetransform2 ( UnivariateRealFunction f , double min , double max , int n ) throws IllegalArgumentException , FunctionEvaluationException { } public Complex [ ] inversetransform2 ( Complex [ ] f ) throws IllegalArgumentException { } protected Complex [ ] fft ( double [ ] f , boolean isInverse ) throws IllegalArgumentException { } protected Complex [ ] fft ( Complex [ ] data ) throws IllegalArgumentException { } public static double [ ] sample ( UnivariateRealFunction f , double min , double max , int n ) throws IllegalArgumentException , FunctionEvaluationException { } public static double [ ] scaleArray ( double [ ] f , double d ) { } public static Complex [ ] scaleArray ( Complex [ ] f , double d ) { } public static boolean isPowerOf2 ( long n ) { } public static void verifyDataSet ( double [ ] d ) throws IllegalArgumentException { } public static void verifyDataSet ( Object [ ] o ) throws IllegalArgumentException { } public static void verifyInterval ( double lower , double upper ) throws IllegalArgumentException { } public Object mdfft ( Object mdca , boolean forward ) throws IllegalArgumentException { } private void mdfft ( FastFourierTransformer . MultiDimensionalComplexMatrix mdcm , boolean forward , int d , int [ ] subVector ) throws IllegalArgumentException { } private class MultiDimensionalComplexMatrix implements Serializable , Cloneable { private static final long serialVersionUID = 6219415319201978011L ; protected int [ ] dimensionSize = new int [ 1 ] ; protected Object multiDimensionalComplexArray ; public MultiDimensionalComplexMatrix ( Object multiDimensionalComplexArray ) { } public Complex get ( int ... vector ) throws IllegalArgumentException { } public Complex set ( Complex magnitude , int ... vector ) throws IllegalArgumentException { if ( vector == null ) { if ( ( dimensionSize . length ) > 1 ) { throw MathRuntimeException . createIllegalArgumentException ( "some<seq2seq4repair_space>dimensions<seq2seq4repair_space>don't<seq2seq4repair_space>math:<seq2seq4repair_space>{0}<seq2seq4repair_space>!=<seq2seq4repair_space>{1}" , 0 , dimensionSize . length ) ; } return null ; } <START_BUG> if ( ( vector != null ) && ( ( vector . length ) != ( dimensionSize . length ) ) ) { <END_BUG> throw MathRuntimeException . createIllegalArgumentException ( "some<seq2seq4repair_space>dimensions<seq2seq4repair_space>don't<seq2seq4repair_space>math:<seq2seq4repair_space>{0}<seq2seq4repair_space>!=<seq2seq4repair_space>{1}" , vector . length , dimensionSize . length ) ; } Object [ ] lastDimension = ( ( Object [ ] ) ( multiDimensionalComplexArray ) ) ; for ( int i = 0 ; i < ( ( dimensionSize . length ) - 1 ) ; i ++ ) { lastDimension = ( ( Object [ ] ) ( lastDimension [ vector [ i ] ] ) ) ; } Complex lastValue = ( ( Complex ) ( lastDimension [ vector [ ( ( dimensionSize . length ) - 1 ) ] ] ) ) ; lastDimension [ vector [ ( ( dimensionSize . length ) - 1 ) ] ] = magnitude ; return lastValue ; } public int [ ] getDimensionSizes ( ) { } public Object getArray ( ) { } @ Override public Object clone ( ) { } private void clone ( FastFourierTransformer . MultiDimensionalComplexMatrix mdcm ) { } } private static class RootsOfUnity implements Serializable { private static final long serialVersionUID = 6404784357747329667L ; private int omegaCount ; private double [ ] omegaReal ; private double [ ] omegaImaginaryForward ; private double [ ] omegaImaginaryInverse ; private boolean isForward ; public RootsOfUnity ( ) { } public synchronized boolean isForward ( ) throws IllegalStateException { } public synchronized void computeOmega ( int n ) throws IllegalArgumentException { } public synchronized double getOmegaReal ( int k ) throws IllegalArgumentException , IllegalStateException { } public synchronized double getOmegaImaginary ( int k ) throws IllegalArgumentException , IllegalStateException { } } }

Fix:
if ( ( vector . length ) != ( dimensionSize . length ) ) {